*Note that the resulting image size can differ from the paper size it is printed on, as it will be the maximum fit of the image onto your chosen paper size including a minimum small white border around the image.

Photograph Description

This moon is Saturn’s third largest, with a diameter of around 1470 kilometres. It is mostly composed of ice. A combination of thermal and orbital effects have led over billions of years to the leading side (left) retaining a dark dust layer, while the ice of the trailing side (right) is mostly dust free. Iapetus’s prominent equatorial bulge and impact craters (Engelier at bottom in the image at right) are also seen. These images were obtained on 10 September 2007 (right) and 27 December 2004 (left), by the narrow-angle camera on the Cassini spacecraft that is in orbit around Saturn. (Photo by Science Photo Library)